U.S. patent application number 12/494871 was filed with the patent office on 2010-05-06 for methods and devices for treating urinary incontinence.
Invention is credited to Charles S. Carignan, Stuart D. Edwards, Simon Thomas.
Application Number | 20100114087 12/494871 |
Document ID | / |
Family ID | 42132327 |
Filed Date | 2010-05-06 |
United States Patent
Application |
20100114087 |
Kind Code |
A1 |
Edwards; Stuart D. ; et
al. |
May 6, 2010 |
METHODS AND DEVICES FOR TREATING URINARY INCONTINENCE
Abstract
Described herein are devices, systems and methods for treatment
of tissue within a lumen of a body. For example, the devices
described herein may be used to treat the urethra or
gastrointestinal tract, including a sphincter. These devices may
provide an expandable element at the distal end of an elongate body
and may also include a plurality of electrodes (e.g., needle
electrodes) configured to extend from the device and into the
tissue to deliver energy to multiple, circumferentially arranged
treatment sites. Sufficient energy may be delivered from the device
to create a desired tissue effect.
Inventors: |
Edwards; Stuart D.;
(Salinas, CA) ; Carignan; Charles S.; (Boston,
MA) ; Thomas; Simon; (Newark, CA) |
Correspondence
Address: |
SHAY GLENN LLP
2755 CAMPUS DRIVE, SUITE 210
SAN MATEO
CA
94403
US
|
Family ID: |
42132327 |
Appl. No.: |
12/494871 |
Filed: |
June 30, 2009 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11651750 |
Jan 10, 2007 |
|
|
|
12494871 |
|
|
|
|
09924935 |
Aug 8, 2001 |
7165551 |
|
|
11651750 |
|
|
|
|
09360599 |
Jul 26, 1999 |
|
|
|
09924935 |
|
|
|
|
09026085 |
Feb 19, 1998 |
|
|
|
09360599 |
|
|
|
|
09026296 |
Feb 19, 1998 |
6009877 |
|
|
09026085 |
|
|
|
|
Current U.S.
Class: |
606/33 |
Current CPC
Class: |
A61B 18/1477 20130101;
A61B 2018/00738 20130101; A61B 2018/046 20130101; A61M 25/1002
20130101; A61B 2018/00553 20130101; A61M 2025/0087 20130101; A61B
8/445 20130101; A61B 18/1492 20130101; A61B 8/0833 20130101; A61B
18/1485 20130101; A61B 2034/2063 20160201; A61M 2025/0086 20130101;
A61B 8/12 20130101; A61B 2017/22074 20130101; A61B 2018/00267
20130101; A61B 90/39 20160201; A61B 2018/00011 20130101; A61B
2018/00791 20130101; A61B 2018/00214 20130101; A61B 2017/00469
20130101; A61B 2090/3925 20160201; A61B 2018/00505 20130101; A61B
2018/00702 20130101; A61B 2017/00805 20130101 |
Class at
Publication: |
606/33 |
International
Class: |
A61B 18/18 20060101
A61B018/18 |
Claims
1. A device for delivering energy to a treatment site in an annular
pattern of circumferentially spaced-apart regions in the tissue of
a body, the device comprising: an elongate shaft; an expandable
member near the distal end of the elongate shaft configured to
secure the treatment device within the body; a plurality of needle
electrodes configured to extend from the device to contact tissue
in an annular array that is circumferentially spaced about the
axis, each electrode configured to transmit radio frequency energy
to the tissue; and a temperature sensor for sensing the temperature
of the tissue at a treatment site.
2. The device of claim 1, further comprising a fluid channel for
delivery of a fluid from the device.
3. The device of claim 1, further comprising a fluid channel
through each of the needle electrodes configured for delivery of a
fluid.
4. The device of claim 1, further comprising a handle at the
proximal end of the device configured to manipulate the device.
5. The device of claim 1, wherein the expandable member comprises a
basket assembly.
6. The device of claim 1, wherein the expandable member comprises a
balloon.
7. The device of claim 1, further comprising a plurality of
temperature sensors.
8. The device of claim 1, further comprising a distal cap.
9. A system for delivering energy to a treatment site in an annular
pattern of circumferentially spaced-apart regions in the tissue of
a body, the system comprising: a treatment device comprising: an
elongate shaft; an expandable member near the distal end of the
elongate shaft; a plurality of needle electrodes configured to
penetrate the tissue in an annular array that is circumferentially
spaced about the axis of the elongate shaft, each electrode
configured to transmit radio frequency energy to the tissue; and a
temperature sensor; a power source configured to provide radio
frequency energy to treatment device; a controller configured to
supply radio frequency energy from the power source at to the
needle electrodes to treat the tissue in an annular pattern of
individual, circumferentially spaced-apart tissue regions, the
controller being coupled to the temperature sensor to control the
power supplied by the power source to the electrodes.
10. The system of claim 9, wherein the treatment device further
comprises a fluid channel for delivery of a fluid from the
treatment device.
11. The system of claim 9, wherein the treatment device further
comprises a handle at the proximal end of the treatment device
configured to manipulate the treatment device.
12. The system of claim 9, wherein the expandable member of the
treatment device comprises a basket assembly.
13. The system of claim 9, wherein the expandable member of the
treatment device comprises a balloon.
14. The system of claim 9, wherein the plurality of needle
electrodes are configured to controllably extend from the
shaft.
15. The system of claim 9, wherein the temperature sensor is
located adjacent to the needle electrodes and is configured to
sense the temperature of the tissue at a treatment site.
16. A method of delivering energy to a tissue in an annular pattern
of circumferentially spaced-apart treatment sites in the tissue of
a patient's body, the method comprising: providing a treatment
device having a plurality of tissue-piercing needle electrodes
configured to extend from the treatment device and an expandable
member at the distal end of the treatment device; advancing the
treatment device distally within a lumen in a patient's body to a
treatment site; expanding the expandable member; extending the
tissue-piercing needle electrodes from the treatment device into
the tissue; and delivering RF energy from the needle electrodes in
an annular pattern of individual, circumferentially spaced-apart
tissue regions.
17. The method of claim 16, further comprising the step of pulling
proximally upon the treatment device until resistance to the
pulling is encountered before extending the tissue-piercing needle
electrodes.
18. The method of claim 16, further comprising introducing a
cooling fluid to cool tissue adjacent to the treatment site.
19. The method of claim 16, further comprising sensing a tissue
temperature, and controlling delivery of RF energy based, at least
in part, upon the sensed tissue temperature condition.
20. The method of claim 16, wherein the step of advancing the
treatment device distally comprises advancing the treatment device
within a patient's urethra.
21. The method of claim 16, wherein the step of delivering RF
energy comprises producing a plurality of submucosal lesions in an
annular pattern of individual, circumferentially spaced-apart
tissue regions.
22. A method of delivering energy to a tissue in an annular pattern
of circumferentially spaced-apart treatment sites in the tissue in
a patient's urethra, the method comprising: providing a treatment
device having a plurality of tissue-piercing needle electrodes
configured to extend from the treatment device and an expandable
member at the distal end of the treatment device; advancing the
treatment device distally within a patient's urethra; expanding the
expandable member within the patient's bladder; extending at least
one tissue-piercing needle electrode from the treatment device into
the tissue; and delivering RF energy from the needle electrodes in
an annular pattern of individual, circumferentially spaced-apart
tissue regions.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority as a Continuation-in-Part
of pending U.S. patent application Ser. No. 11/420,712, filed on
May 26, 2006 and titled "SYSTEM FOR TISSUE ABLATION", which is a
continuation application of U.S. patent application Ser. No.
10/963,025, filed Oct. 12, 2004 (titled "METHODS FOR TREATING THE
CARDIA OF THE STOMACH"), which is a divisional of U.S. patent
application Ser. No. 10/247,153, filed Sep. 19, 2002 (titled
"METHODS FOR TREATING THE CARDIA OF THE STOMACH"), now U.S. Pat.
No. 6,872,206, which is a divisional of U.S. patent application
Ser. No. 09/304,737, filed May 4, 1999 (titled "STOMACH AND
ADJOINING TISSUE REGIONS IN THE ESOPHAGUS"), now U.S. Pat. No.
6,464,697, which is a continuation-in-part of U.S. patent
application Ser. No. 09/026,296, filed Feb. 19, 1998 (titled
"METHOD FOR TREATING A SPHINCTER"), now U.S. Pat. No. 6,009,877, to
which applications we claim priority under 35 U.S.C. .sctn.120.
INCORPORATION BY REFERENCE
[0002] All publications and patent applications mentioned in this
specification are herein incorporated by reference in their
entirety to the same extent as if each individual publication or
patent application was specifically and individually indicated to
be incorporated by reference.
FIELD OF THE INVENTION
[0003] This invention relates generally to devices and methods for
the treatment of tissue within a body, and more specifically to
devices and methods that may be used to treat urinary incontinence
and esophageal sphincters.
BACKGROUND OF THE INVENTION
[0004] Many disorders and diseases may benefit from the delivery of
therapies that apply localized tissue treatment that can be applied
through a body orifice. For example, urinary incontinence (UI) and
gastroesophageal reflux disease (GERD) may both benefit from the
controlled application of energy to tissue associated body
regions.
[0005] GERD is a common gastroesophageal disorder in which the
stomach contents are ejected into the lower esophagus due to a
dysfunction of the lower esophageal sphincter (LES). These contents
are highly acidic and potentially injurious to the esophagus
resulting in a number of possible complications of varying medical
severity. The reported incidence of GERD in the U.S. is as high as
10% of the population (Castell D O; Johnston B T: Gastroesophageal
Reflux Disease: Current Strategies For Patient Management. Arch Fam
Med, 5(4):221-7; (1996 April)).
[0006] Acute symptoms of GERD include heartburn, pulmonary
disorders and chest pain. On a chronic basis, GERD subjects the
esophagus to ulcer formation, or esophagitis and may result in more
severe complications including esophageal obstruction, significant
blood loss and perforation of the esophagus. Severe esophageal
ulcerations occur in 20-30% of patients over age 65. Moreover, GERD
causes adenocarcinoma, or cancer of the esophagus, which is
increasing in incidence faster than any other cancer (Reynolds J C:
Influence Of Pathophysiology, Severity, And Cost On The Medical
Management Of Gastroesophageal Reflux Disease. Am J Health Syst
Pharm, 53(22 Suppl 3):S5-12 (Nov. 15, 1996)).
[0007] One of the possible causes of GERD may be aberrant
electrical signals in the LES or cardia of the stomach. Such
signals may cause a higher than normal frequency of relaxations of
the LES allowing acidic stomach contents to be repeatedly ejected
into the esophagus and cause the complications described above.
Research has shown that unnatural electrical signals in the stomach
and intestine can cause reflux events in those organs (Kelly K A,
et al: Duodenal-gastric Reflux and Slowed Gastric Emptying by
Electrical Pacing of the Canine Duodenal Pacesetter Potential.
Gastroenterology. 1977 March; 72(3): 429-433). In particular,
medical research has found that sites of aberrant electrical
activity or electrical foci may be responsible for those signals
(Karlstrom L H, et al.: Ectopic Jejunal Pacemakers and
Enterogastric Reflux after Roux Gastrectomy: Effect Intestinal
Pacing. Surgery. 1989 September; 106(3): 486-495). Similar aberrant
electrical sites in the heart which cause contractions of the heart
muscle to take on life threatening patterns or dysrhythmias can be
identified and treated using mapping and ablation devices as
described in U.S. Pat. No. 5,509,419. However, there is no current
device or associated medical procedure available for the electrical
mapping and treatment of aberrant electrical sites in the LES and
stomach as a means for treating GERD.
[0008] Current drug therapy for GERD includes histamine receptor
blockers which reduce stomach acid secretion and other drugs which
may completely block stomach acid. However, while pharmacologic
agents may provide short term relief, they do not address the
underlying cause of LES dysfunction.
[0009] Invasive procedures requiring percutaneous introduction of
instrumentation into the abdomen exist for the surgical correction
of GERD. One such procedure, Nissen fundoplication, involves
constructing a new "valve" to support the LES by wrapping the
gastric fundus around the lower esophagus. Although the operation
has a high rate of success, it is an open abdominal procedure with
the usual risks of abdominal surgery including: postoperative
infection, herniation at the operative site, internal hemorrhage
and perforation of the esophagus or of the cardia. In fact, a
recent 10 year, 344 patient study reported the morbidity rate for
this procedure to be 17% and mortality 1% (Urschel, J D:
Complications Of Antireflux Surgery, Am J Surg 166(1): 68-70; (July
1993)). This rate of complication drives up both the medical cost
and convalescence period for the procedure and may exclude portions
of certain patient populations (e.g., the elderly and
immuno-compromised).
[0010] Efforts to perform Nissen fundoplication by less invasive
techniques have resulted in the development of laparoscopic Nissen
fundoplication. Laparoscopic Nissen fundoplication, reported by
Dallemagne et al. Surgical Laparoscopy and Endoscopy, Vol. 1, No.
3, (1991), pp. 138-43 and by Hindler et al. Surgical Laparoscopy
and Endoscopy, Vol. 2, No. 3, (1992), pp. 265-272, involves
essentially the same steps as Nissen fundoplication with the
exception that surgical manipulation is performed through a
plurality of surgical cannula introduced using trocars inserted at
various positions in the abdomen.
[0011] Another attempt to perform fundoplication by a less invasive
technique is reported in U.S. Pat. No. 5,088,979. In this procedure
an invagination device containing a plurality of needles is
inserted transorally into the esophagus with the needles in a
retracted position. The needles are extended to engage the
esophagus and fold the attached esophagus beyond the
gastroesophageal junction. A remotely operated stapling device,
introduced percutaneously through an operating channel in the
stomach wall, is actuated to fasten the invaginated
gastroesophageal junction to the surrounding involuted stomach
wall.
[0012] Yet another attempt to perform fundoplication by a less
invasive technique is reported in U.S. Pat. No. 5,676,674. In this
procedure, invagination is done by a jaw-like device and fastening
of the invaginated gastroesophageal junction to the fundus of the
stomach is done via a transoral approach using a remotely operated
fastening device, eliminating the need for an abdominal incision.
However, this procedure is still traumatic to the LES and presents
the postoperative risks of gastroesophageal leaks, infection and
foreign body reaction, the latter two sequela resulting when
foreign materials such as surgical staples are implanted in the
body.
[0013] While the methods reported above are less invasive than an
open Nissen fundoplication, some still involve making an incision
into the abdomen and hence the increased morbidity and mortality
risks and convalescence period associated with abdominal surgery.
Others incur the increased risk of infection associated 20 with
placing foreign materials into the body. All involve trauma to the
LES and the risk of leaks developing at the newly created
gastroesophageal junction.
[0014] Besides the LES, there are other sphincters in the body
which, if not functionally properly can cause disease states or
otherwise adversely affect the lifestyle of the patient. Reduced
muscle tone or otherwise aberrant relaxation of sphincters can
result in a laxity of tightness disease states including, but not
limited to, urinary incontinence.
[0015] Urinary incontinence arises in both women and men with
varying degrees of severity, and from different causes. In men, the
condition occurs most often as a result of prostatectomies which
result in mechanical damage to the sphincter. In women, the
condition typically arises after pregnancy where musculoskeletal
damage has occurred as a result of inelastic stretching of the
structures which support the genitourinary tract. Specifically,
pregnancy can result in inelastic stretching of the pelvic floor,
the external sphincter, and most often, to the tissue structures
which support the bladder and bladder neck region. In each of these
cases, urinary leakage typically occurs when a patient's
intra-abdominal pressure increases as a result of stress, e.g.
coughing, sneezing, laughing, exercise, or the like.
[0016] Treatment of urinary incontinence can take a variety of
forms. Most simply, the patient can wear absorptive devices or
clothing, which is often sufficient for minor leakage events.
Alternatively or additionally, patients may undertake exercises
intended to strengthen the muscles in the pelvic region, or may
attempt behavior modification intended to reduce the incidence of
urinary leakage.
[0017] In cases where such non-interventional approaches are
inadequate or unacceptable, the patient may undergo surgery to
correct the problem. A variety of procedures have been developed to
correct urinary incontinence in women. Several of these procedures
are specifically intended to support the bladder neck region. For
example, sutures, straps, or other artificial structures are often
looped around the bladder neck and affixed to the pelvis, the
endopelvic fascia, the ligaments which support the bladder, or the
like. Other procedures involve surgical injections of bulking
agents, inflatable balloons, or other elements to mechanically
support the bladder neck.
[0018] Each of these procedures has associated shortcomings.
Surgical operations which involve suturing of the tissue structures
supporting the urethra or bladder neck region require great skill
and care to achieve the proper level of artificial support. In
other words, it is necessary to occlude or support the tissues
sufficiently to inhibit urinary leakage, but not so much that
intentional voiding is made difficult or impossible. Balloons and
other bulking agents which have been inserted can migrate or be
absorbed by the body. The presence of such inserts can also be a
source of urinary tract infections. Therefore, it would be
desirable to provide an improved therapy for urinary
incontinence.
[0019] A variety of other problems can arise when the support
tissues of the body have excessive length. Excessive length of the
pelvic support tissues (particularly the ligaments and fascia of
the pelvic area) can lead to a variety of ailments including, for
example, cystocele, in which a portion of the bladder protrudes
into the vagina. Excessive length of the tissues supporting the
breast may cause the breasts to sag. Many hernias are the result of
a strained, torn, and/or distended containing tissue, which allows
some other tissue or organ to protrude beyond its contained
position. Cosmetic surgeries are also often performed to decrease
the length of support tissues. For example, abdominoplasty (often
called a "tummy tuck") is often performed to decrease the
circumference of the abdominal wall. The distortion of these
support tissues may be due to strain, advanced age, congenital
predisposition, or the like.
[0020] Unfortunately, many support tissues are difficult to access,
and their tough, fibrous nature can complicate their repair. As a
result, the therapies now used to improve or enhance the support
provided by the ligaments and fascia of the body often involve
quite invasive surgical procedures.
[0021] Thus, it would be desirable to provide improved devices,
methods, and systems for treating disorders such as UI and GERD. In
particular, it would be useful to provide methods, devices and
systems for treating sphincters, fascia, tendons, and the other
support tissues of the body. It would be particularly desirable to
provide minimally invasive therapies for these support tissues,
especially for the treatment of urinary incontinence. It would
further be desirable to provide treatment methods which made use of
the existing support structures of the body, rather than depending
on the specific length of an artificial support structure.
SUMMARY OF THE INVENTION
[0022] The present invention relates to methods, device and systems
for delivery of energy (and particularly RF energy) to a treatment
site such as a boy lumen like the urethra, esophogeous or the like.
Accordingly, an object of the present invention is to provide a
method to treat a lumen using methods, devices and system for
forming an annular pattern of circumferentially spaced-apart
regions. These devices, methods and systems may be applied to treat
sphincters and reduce a frequency of sphincter relaxation.
Treatment of sphincters is one sub-set of the treatment methods
that may be applied by the devices and systems described
herein.
[0023] In general, the treatment methods described herein may be
used to modify the target tissue. For example, the tissue may be
lesioned. A lesion may be a change in the structure of the tissue,
including a change in the elasticity of the tissue, shrinkage of
the tissue, or in some cases necrosis of the tissue. For example,
the application of energy to the target tissue may heat the tissue
(e.g., fascia and other collagenated support tissues), which may
cause them to contract or change elasticity. In some variations,
the tissue may be lesioned or modified without substantial necrosis
of adjacent tissues. In some variations, the tissue may be
necrosed. Thus, in some variations, an object of the invention is
to provide a method to create controlled cell necrosis in a
sphincter tissue underlying a sphincter mucosal layer. In some
variations, an object of the present invention is to modify the
elasticity of the tissue without substantial necrosis of the
tissues.
[0024] As described herein, the energy is provided using a
treatment device that is elongate (e.g., for insertion into a body
lumen) and includes an expandable region (e.g., anchor) and one or
more electrodes such as needle electrodes. These devices may be
configured for extension of the electrodes from the device (e.g.,
the shaft of the device or the expandable member) into the target
tissue to from a circumferential pattern of treatment sites by
applying RF energy from the electrodes. In some variations a
cooling fluid (e.g., water ,saline or glycine) may be applied to or
near the treatment sites to control the heating of the tissue or
limit the heating of adjacent tissues that are not being directly
treated.
[0025] For example, described herein are devices for delivering
energy to a treatment site in an annular pattern of
circumferentially spaced-apart regions in the tissue of a body. The
treatment site may be a region of the esophagus (e.g., a region
having a sphincter) or a region of the urethra. In some variations,
the device includes: an elongate shaft; an expandable member near
the distal end of the elongate shaft configured to secure the
treatment device within the body; a plurality of needle electrodes
configured to extend from the device to contact tissue in an
annular array that is circumferentially spaced about the axis, each
electrode configured to transmit radio frequency energy to the
tissue; and a temperature sensor for sensing the temperature of the
tissue at a treatment site.
[0026] In some variations, the device may also include a fluid
channel for delivery of a fluid from the device. The fluid channel
may be configured to apply a cooling fluid from a proximally
located reservoir. The fluid channel may pass through the elongate
shaft. In some variations, the fluid channel passes through each of
the needle electrodes for delivery of a fluid out of the needle
electrodes.
[0027] The devices described herein may also include a handle at
the proximal end of the device configured to manipulate the device.
The handle may include an attachment to a controller and/or power
supply, one or more connectors to a fluid source, and/or a
connector to a source of vacuum or pressurized gas (e.g., to
inflate the expandable member).
[0028] The expandable member may comprise a basket assembly. For
example, the basket assembly may include a plurality of arms that
can be extended from the elongate body. In some variations, the
expandable member comprises a balloon.
[0029] The devices described herein may include a single
temperature sensor or a plurality of temperature sensors.
[0030] In some variations, the devices may also include a distal
cap. The distal cap may be a protective cap (e.g., an atraumatic
cap) that does not penetrate tissue. The elongate body may also be
flexible.
[0031] Also described herein are systems for delivering energy to a
treatment site in an annular pattern of circumferentially
spaced-apart regions in the tissue of a body. These systems may
include any of the treatment devices described, as well as one or
more power (energy) sources and/or controllers. For example, a
system may include: a treatment device, a power source and a
controller. The treatment device may include: an elongate shaft; an
expandable member near the distal end of the elongate shaft; a
plurality of needle electrodes configured to penetrate the tissue
in an annular array that is circumferentially spaced about the axis
of the elongate shaft, each electrode configured to transmit radio
frequency energy to the tissue; and a temperature sensor. The power
source may be configured to provide radio frequency energy to
treatment device. The controller may be configured to supply radio
frequency energy from the power source at to the needle electrodes
to treat the tissue in an annular pattern of individual,
circumferentially spaced-apart tissue regions, the controller being
coupled to the temperature sensor to control the power supplied by
the power source to the electrodes.
[0032] As mentioned, the treatment device may include a fluid
channel for delivery of a fluid from the treatment device, a handle
at the proximal end of the treatment device configured to
manipulate the treatment device, or the like. The expandable member
of the treatment device may be a basket assembly and/or a
balloon.
[0033] In some variations, the plurality of needle electrodes may
be configured to controllably extend from the shaft. The needle
electrodes may also be configured to extend from (or through) the
expandable element.
[0034] The temperature sensor may be located adjacent to the needle
electrodes and configured to sense the temperature of the tissue at
a treatment site.
[0035] Also described herein are methods of delivering energy to a
tissue in an annular pattern of circumferentially spaced-apart
treatment sites in the tissue of a patient's body. As mentioned,
these methods may be applied to a body lumen, including a urethra
or an esophagus. For example, the method may include the steps of:
providing a treatment device having a plurality of tissue-piercing
needle electrodes configured to extend from the treatment device
and an expandable member at the distal end of the treatment device;
advancing the treatment device distally within a lumen in a
patient's body to a treatment site; expanding the expandable
member; extending the tissue-piercing needle electrodes from the
treatment device into the tissue; and delivering RF energy from the
needle electrodes in an annular pattern of individual,
circumferentially spaced-apart tissue regions.
[0036] The method may also include the step of pulling proximally
upon the treatment device until resistance to the pulling is
encountered before extending the tissue-piercing needle electrodes.
The method may also include the step of introducing a cooling fluid
to cool tissue adjacent to the treatment site.
[0037] In some variations, the method further includes sensing a
tissue temperature, and controlling delivery of RF energy based, at
least in part, upon the sensed tissue temperature condition.
[0038] The step of advancing the treatment device distally may
include advancing the treatment device within a patient's urethra.
The step of delivering RF energy may include producing a plurality
of submucosal lesions in an annular pattern of individual,
circumferentially spaced-apart tissue regions. This may result in
at least partially denaturing collagen in this region.
[0039] In one example, described herein is a method of delivering
energy to a tissue in an annular pattern of circumferentially
spaced-apart treatment sites in the tissue in a patient's urethra,
including the steps of: providing a treatment device having a
plurality of tissue-piercing needle electrodes configured to extend
from the treatment device and an expandable member at the distal
end of the treatment device; advancing the treatment device
distally within a patient's urethra; expanding the expandable
member within the patient's bladder; extending at least one
tissue-piercing needle electrode from the treatment device into the
tissue; and delivering RF energy from the needle electrodes in an
annular pattern of individual, circumferentially spaced-apart
tissue regions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0040] FIG. 1 is an illustrated lateral view of the upper GI tract
including the esophagus and lower esophageal sphincter and the
positioning of a treatment apparatus in the lower esophageal
sphincter.
[0041] FIG. 2 is a lateral view of a treatment apparatus
illustrating an energy delivery device, power supply and expansion
member in an expanded and contracted state.
[0042] FIG. 3 depicts a lateral view of an apparatus that
illustrates components on the flexible shaft including a proximal
fitting, connections and proximal and distal shaft segments.
[0043] FIG. 4 illustrates a lateral view of a basket assembly.
[0044] FIG. 5A is a lateral view of the basket assembly that
illustrates the range of camber in the basket assembly.
[0045] FIG. 5B is a perspective view illustrating a balloon coupled
to the basket assembly.
[0046] FIG. 6A is a lateral view of the junction between the basket
arms and the shaft illustrating the pathway used for advancement of
the movable wire or the delivery of fluids.
[0047] FIG. 6B is a frontal view of a basket arm in an alternative
embodiment of an apparatus, illustrating a track in the arm used to
advance the movable wire.
[0048] FIG. 7 is a cross-sectional view of a section of the basket
arm illustrating stepped and tapered sections in basket arm
apertures.
[0049] FIG. 8 is a lateral view of the basket assembly illustrating
the placement of the radial supporting member.
[0050] FIG. 9A is a lateral view of the sphincter treatment
apparatus, illustrating the mechanism used in one embodiment to
increase the camber of the basket assembly.
[0051] FIG. 9B is a similar view to 9A showing the basket assembly
in an increased state of camber.
[0052] FIG. 10 is a lateral view of a sphincter treatment
apparatus, illustrating the deflection mechanism.
[0053] FIG. 11 is a lateral view illustrating the use of
electrolytic solution to create an enhanced RF electrode.
[0054] FIG. 12 is a lateral view of the basket assembly
illustrating the use of needle electrodes.
[0055] FIG. 13 is a lateral view illustrating the use of an
insulation segment on the needle electrode to protect an area of
tissue from RF energy.
[0056] FIG. 14 is a lateral view illustrating the placement of
needle electrodes into the sphincter wall by expansion of the
basket assembly.
[0057] FIG. 15 is a lateral view illustrating placement of needle
electrodes into the sphincter wall by advancement of an electrode
delivery member out of apertures in the basket arms.
[0058] FIG. 16 is a cross sectional view illustrating the
configuration of a basket arm aperture used to select and maintain
a penetration angle of the needle electrode into the sphincter
wall.
[0059] FIG. 17 is a lateral view illustrating placement of needle
electrodes into the sphincter wall by advancement of an electrode
delivery member directly out of the distal end of the shaft.
[0060] FIG. 18A is a lateral view illustrating a radial
distribution of electrodes on the expansion device useful with the
method of the present invention.
[0061] FIG. 18B is a lateral view illustrating a longitudinal
distribution of electrodes on the expansion device.
[0062] FIG. 18C is a lateral view illustrating a spiral
distribution of electrodes on the expansion device.
[0063] FIG. 19 is a flow chart illustrating the sphincter treatment
method.
[0064] FIG. 20 is a lateral view of sphincter smooth muscle tissue
illustrating electromagnetic foci and pathways for the origination
and conduction of aberrant electrical signals in the smooth muscle
of the lower esophageal sphincter or other tissue.
[0065] FIG. 21 is a lateral view of a sphincter wall illustrating
the infiltration of tissue healing cells into a lesion in the
smooth tissue of a sphincter following treatment with the sphincter
treatment apparatus.
[0066] FIG. 22 is a view similar to that of FIG. 21 illustrating
shrinkage of the lesion site caused by cell infiltration.
[0067] FIG. 23 is a lateral view of the esophageal wall
illustrating the preferred placement of lesions in the smooth
muscle layer of an esophageal sphincter.
[0068] FIG. 24 is a lateral view illustrating the ultrasound
transducer, ultrasound lens and power source of an embodiment of a
treatment device.
[0069] FIGS. 25A-D are lateral views of the sphincter wall
illustrating various patterns of lesions created by a treatment
device.
[0070] FIG. 26 is a lateral view of the sphincter wall illustrating
the delivery of cooling fluid to the electrode-tissue interface and
the creation of cooling zones.
[0071] FIG. 27 depicts the flow path, fluid connections and control
unit employed to deliver fluid to the electrode-tissue
interface.
[0072] FIG. 28 depicts the flow path, fluid connections and control
unit employed to deliver fluid to the RF electrodes.
[0073] FIG. 29 is an enlarged lateral view illustrating the
placement of sensors on the expansion device or basket
assembly.
[0074] FIG. 30 depicts a block diagram of the feedback control
system that can be used with the treatment apparatus.
[0075] FIG. 31 depicts a block diagram of an analog amplifier,
analog multiplexer and microprocessor used with the feedback
control system of FIG. 30.
[0076] FIG. 32 depicts a block diagram of the operations performed
in the feedback control system depicted in FIG. 30.
[0077] FIG. 33 is a block diagram of another variation of a method
of treating a body lumen.
DETAILED DESCRIPTION OF THE INVENTION
[0078] The devices described herein may be referred to treatment
devices, as treatment apparatus, as sphincter treatment devices, as
sphincter treatment apparatus, or as urethra treatment devices. Any
of these devices may be used to treat a body lumen, including, but
not limited to the urethra and the gastrointestinal tract. In
general, these devices include an elongate body, an expandable
distal region, and a plurality of energy-emitting regions (e.g.,
needle electrodes).
[0079] For example, referring now to FIGS. 1 and 2, one embodiment
of treatment apparatus 10 that is used to deliver energy to a
treatment site 12 to produce lesions 14 in lumen, including lumen
having a sphincter 16, such as the lower esophageal sphincter
(LES), comprises a flexible elongate shaft 18, also called shaft
18, coupled to a expansion device 20, in turn coupled with one or
more energy delivery devices 22. Energy delivery devices 22 are
configured to be coupled to a power source 24. The expansion device
20 is configured to be positionable in a sphincter 16 such as the
LES or adjacent anatomical structure, such as the cardia of the
stomach. Expansion device 20 is further configured to facilitate
the positioning of energy delivery devices 22 to a selectable depth
in a sphincter wall 26 or adjoining anatomical structure. Expansion
device 20 has a central longitudinal axis 28 and is moveable
between contracted and expanded positions substantially there
along. This can be accomplished by a ratchet mechanism as is known
to those skilled in the art. At least portions of sphincter
treatment apparatus 10 may be sufficiently radiopaque in order to
be visible under fluoroscopy and/or sufficiently echogenic to be
visible under ultrasonography. Also as will be discussed herein,
sphincter treatment apparatus 10 can include visualization
capability including, but not limited to, a viewing scope, an
expanded eyepiece, fiber optics, video imaging and the like.
[0080] Referring to FIG. 2, shaft 18 is configured to be coupled to
expansion device 20 and has sufficient length to position expansion
device 20 in the LES and/or stomach using a transoral approach.
Typical lengths for shaft 18 include, but are not limited to, a
range of 40-180 cms. In various embodiments, shaft 18 is flexible,
articulated and steerable and can contain fiber optics (including
illumination and imaging fibers, fluid and gas paths, and sensor
and electronic cabling. In one embodiment, shaft 18 can be a
multi-lumen catheter, as is well known to those skilled in the art.
In another embodiment, an introducing member 21, also called an
introducer, is used to introduce sphincter treatment apparatus 10
into the LES. Introducer 21 can also function as a sheath for
expansion device 20 to keep it in a nondeployed or contracted state
during introduction into the LES. In various embodiments,
introducer 21 is flexible, articulated and steerable and contains a
continuous lumen of sufficient diameter to allow the advancement of
sphincter treatment apparatus 10. Typical diameters for introducer
21 include 0.1 to 2 inches, while typical lengths include 40-180
cms. Suitable materials for introducer 21 include coil-reinforced
plastic tubing as is well known to those skilled in the art.
[0081] Referring now to FIG. 3, the flexible elongate shaft 18 is
circular in cross section and has proximal and distal extremities
(also called ends) 30 and 32. Shaft 18 may also be coupled at its
proximal end 32 to a proximal fitting 34, also called a handle,
used by the physician to manipulate treatment apparatus 10 to reach
treatment site 12. Shaft 18 may have one or more lumens 36 that
extend the full length of shaft 18, or part way from shaft proximal
end 30 to shaft distal end 32. Lumens 36 may be used as paths for
catheters, guide wires, pull wires, insulated wires and cabling,
fluid and optical fibers. Lumens 36 are connected to and/or
accessed by connections 38 on or adjacent to proximal fitting 34.
Connections 38 can include luer-lock, lemo connector, swage and
other mechanical varieties well known to those skilled in the art.
Connections 38 can also include optical/video connections which
allow optical and electronic coupling of optical fibers and/or
viewing scopes to illuminating sources, eye pieces and video
monitors. In various embodiments, shaft 18 may stop at the proximal
extremity 40 of expansion device 20 or extend to, or past, the
distal extremity 42 of expansion device 20. Suitable materials for
shaft 18 include, but are not limited to, polyethylenes,
polyurethanes and other medical plastics known to those skilled in
the art.
[0082] Referring now to FIG. 4, in one embodiment of the present
invention, expansion device 20 comprises one or more elongated arms
44 that are joined at their proximal ends 46 and distal ends 48 to
form a basket assembly 50. Proximal arm end 46 is attached to a
supporting structure, which can be the distal end 32 of shaft 18 or
a proximal cap 51. Likewise, distal arm end 48 is also attached to
a supporting structure which can be a basket cap 52 or shaft 18.
Attached arms 44 may form a variety of geometric shapes including,
but not limited to, curved, rectangular, trapezoidal and
triangular. Arms 44 can have a variety of cross sectional
geometries including, but not limited to, circular, rectangular and
crescent-shaped. Also, arms 44 are of a sufficient number (two or
more), and have sufficient spring force (0.01 to 0.5 lbs. force) so
as to collectively exert adequate force on sphincter wall 26 to
sufficiently open and efface the folds of sphincter 16 to allow
treatment with sphincter treatment apparatus 10, while preventing
herniation of sphincter wall 26 into the spaces 53 between arms 44.
Suitable materials for arms 44 include, but are not limited to,
spring steel, stainless steel, superelastic shape memory metals
such as nitinol or wire reinforced plastic tubing as is well known
to those skilled in the art.
[0083] Referring to FIG. 5A, arms 44 can have an outwardly bowed
shaped memory for expanding the basket assembly into engagement
with a lumen or body region, including a subject's bladder,
urethra, or sphincter wall 26 with the amount of bowing, or camber
54 being selectable from a range 0 to 2 inches from longitudinal
axis 28 of basket assembly 50. For the case of a curve-shaped arm
44', expanded arms 44' are circumferentially and symmetrically
spaced-apart.
[0084] In another embodiment shown in FIG. 5B, an expandable member
55, which can be a balloon, is coupled to an interior or exterior
of basket assembly 50. Balloon 55 is also coupled to and inflated
by lumen 36 using gas or liquid. In various other embodiments (not
shown), arms 44 may be asymmetrically spaced and/or distributed on
an arc less than 360.degree. . Also, arms 44 may be preshaped at
time of manufacture or shaped by the physician. In some variations
the expandable member includes only a balloon, and does not also
include a basket.
[0085] Referring now to FIG. 6A, arms 44 may also be solid or
hollow with a continuous lumen 58 that may be coupled with shaft
lumens 36. These coupled lumens provide a path for the delivery of
a fluid or electrode delivery member 60 from shaft 18 to any point
on basket assembly 50. In various embodiments electrode delivery
member 60 can be an insulated wire, an insulated guide wire, a
plastic-coated stainless steel hypotube with internal wiring or a
plastic catheter with internal wiring, all of which are known to
those skilled in the art. As shown in FIG. 6B, arms 44 may also
have a partially open channel 62, also called a track 62, that
functions as a guide track for electrode delivery member 60.
Referring back to FIG. 6A, arms 44 may have one or more apertures
64 at any point along their length that permit the controlled
placement of energy delivery devices 22 at or into sphincter wall
26. Referring now to FIG. 7, apertures 64 may have tapered sections
66 or stepped sections 68 in all or part of their length, that are
used to control the penetration depth of energy delivery devices 22
into sphincter wall 26. Referring back to FIG. 6A, apertures 64 in
combination with arm lumens 58 and shaft lumens 36 may be used for
the delivery of cooling solution 70 or electrolytic solution 72 to
treatment site 12 as described herein. Additionally, arms 44 can
also carry a plurality of longitudinally spaced apart radiopaque
and or echogenic markers or traces, not shown in the drawings,
formed of suitable materials to permit viewing of basket assembly
50 via fluoroscopy or ultrasonography. Suitable radiopaque
materials include platinum or gold, while suitable echogenic
materials include gas filled micro-particles as described in U.S.
Pat. Nos. 5,688,490 and 5,205,287. Arms 44 may also be color-coded
to facilitate their identification via visual medical imaging
methods and equipment, such as endoscopic methods, which are well
known to those skilled in the art.
[0086] In another embodiment of the present invention, a supporting
member 74 is attached to two or more arms 44. Supporting member 74,
also called a strut, can be attached to arms 44 along a
circumference of basket assembly 50 as shown in FIG. 8. Apertures
64 can extend through radial supporting member 74 in one or more
places. Radial supporting member 74 serves the following functions:
i) facilitates opening and effacement of the folds of sphincter 16,
ii) enhances contact of Apertures 64 with sphincter wall 26; and,
iii) reduces or prevents the tendency of arms 44 to bunch up. The
cross sectional geometry of radial supporting member 74 can be
rectangular or circular, though it will be appreciated that other
geometries are equally suitable.
[0087] In one embodiment shown in FIG. 9, arms 44 are attached to
basket cap 52 that in turn, moves freely over shaft 18, but is
stopped distally by shaft cap 78. One or more pull wires 80 are
attached to basket cap 52 and also to a movable fitting 82 in
proximal fitting 34 of sphincter treatment apparatus 10. When pull
wire 80 is pulled back by movable fitting 82, the camber 54 of
basket assembly 50 increases to 54', increasing the force and the
amount of contact applied by basket assembly 50 to sphincter wall
26 or an adjoining structure. Basket assembly 50 can also be
deflected from side to side using deflection mechanism 80. This
allows the physician to remotely point and steer the basket
assembly within the body. In one embodiment shown in FIG. 10,
deflection mechanism 84 includes a second pull wire 80' attached to
shaft cap 78 and also to a movable slide 86 integral to proximal
fitting 34.
[0088] Turning now to a discussion of energy delivery, suitable
power sources 24 and energy delivery devices 22 that can be
employed in one or more embodiments of the invention include: (i) a
radio-frequency (RF) source coupled to an RF electrode, (ii) a
coherent source of light coupled to an optical fiber, (iii) an
incoherent light source coupled to an optical fiber, (iv) a heated
fluid coupled to a catheter with a closed channel configured to
receive the heated fluid, (v) a heated fluid coupled to a catheter
with an open channel configured to receive the heated fluid, (vi) a
cooled fluid coupled to a catheter with a closed channel configured
to receive the cooled fluid, (vii) a cooled fluid coupled to a
catheter with an open channel configured to receive the cooled
fluid, (viii) a cryogenic fluid, (ix) a resistive heating source,
(x) a microwave source providing energy from 915 MHz to 2.45 GHz
and coupled to a microwave antenna, (xi) an ultrasound power source
coupled to an ultrasound emitter, wherein the ultrasound power
source produces energy in the range of 300 KHZ to 3 GHz, or (xii) a
microwave source. For ease of discussion for the remainder of this
application, the power source utilized is an RF source and energy
delivery device 22 is one or more RF electrodes 88, also described
as electrodes 88. However, all of the other herein mentioned power
sources and energy delivery devices are equally applicable to
treatment apparatus 10.
[0089] For the case of RF energy, RF electrode 88 may operated in
either bipolar or monopolar mode with a ground pad electrode. In a
monopolar mode of delivering RF energy, a single electrode 88 is
used in combination with an indifferent electrode patch that is
applied to the body to form the other electrical contact and
complete an electrical circuit. Bipolar operation is possible when
two or more electrodes 88 are used. Multiple electrodes 88 may be
used. These electrodes may be cooled as described herein.
Electrodes 88 can be attached to electrode delivery member 60 by
the use of soldering methods which are well known to those skilled
in the art. Suitable solders include Megabond Solder supplied by
the Megatrode Corporation (Milwaukee, Wis.).
[0090] Suitable electrolytic solutions 72 include saline, solutions
of calcium salts, potassium salts, and the like. Electrolytic
solutions 72 may enhance the electrical conductivity of the
targeted tissue at the treatment site 12. When a highly conductive
fluid such as electrolytic solution 72 is infused into tissue the
electrical resistance of the infused tissue is reduced, in turn,
increasing the electrical conductivity of the infused tissue. As a
result, there will be little tendency for tissue surrounding
electrode 88 to desiccate (a condition described herein that
increases the electrical resistance of tissue) resulting in a large
increase in the capacity of the tissue to carry RF energy.
Referring to FIG. 11, a zone of tissue which has been heavily
infused with a concentrated electrolytic solution 72 can become so
conductive as to actually act as an enhanced electrode 88'. The
effect of enhanced electrode 88' is to increase the amount of
current that can be conducted to the treatment site 12, making it
possible to heat a much greater volume of tissue in a given time
period.
[0091] Also when the power source is RF, power source 24, which
will now be referred to as RF power source 24, may have multiple
channels, delivering separately modulated power to each electrode
88. This reduces preferential heating that occurs when more energy
is delivered to a zone of greater conductivity and less heating
occurs around electrodes 88 which are placed into less conductive
tissue. If the level of tissue hydration or the blood infusion rate
in the tissue is uniform, a single channel RF power source 24 may
be used to provide power for generation of lesions 14 relatively
uniform in size.
[0092] Electrodes 88 can have a variety of shapes and sizes.
Possible shapes include, but are not limited to, circular,
rectangular, conical and pyramidal. Electrode surfaces can be
smooth or textured and concave or convex. The conductive surface
area of electrode 88 can range from 0.1 mm.sup.2 to 100 cm.sup.2.
It will be appreciated that other geometries and surface areas may
be equally suitable. In one embodiment, electrodes 88 can be in the
shape of needles and of sufficient sharpness and length to
penetrate into the smooth muscle of the esophageal wall, sphincter
16 or other anatomical structure. In this embodiment shown in FIGS.
12 and 13, needle electrodes 90 are attached to arms 44 and have an
insulating layer 92, covering an insulated segment 94 except for an
exposed segment 95. For purposes of this disclosure, an insulator
or insulation layer is a barrier to either thermal, RF or
electrical energy flow. Insulated segment 94 is of sufficient
length to extend into sphincter wall 26 and minimize the
transmission of RF energy to a protected site 97 near or adjacent
to insulated segment 94 (see FIG. 13). Typical lengths for
insulated segment 94 include, but are not limited to, 1-4 mms.
Suitable materials for needle electrodes 90 include, but are not
limited to, 304 stainless steel and other stainless steels known to
those skilled in the art. Suitable materials for insulating layer
92 include, but are not limited to, polyimides and polyamides.
[0093] During introduction of treatment apparatus 10, basket
assembly 50 is in a contracted state. Once sphincter treatment
apparatus 10 is properly positioned at the treatment site 12,
needle electrodes 90 are deployed by expansion of basket assembly
50. In one variation of the use of the device to treat a sphincter
in the gastrointestinal tract, this results in the protrusion of
needle electrodes 90 into the smooth muscle tissue of sphincter
wall 26 (refer to FIG. 14). The depth of needle penetration is
selectable from a range of 0.5 to 5 mms and is accomplished by
indexing movable fitting 82 so as to change the camber 54 of arm 44
in fixed increments that can be selectable in a range from 0.1 to 4
mms. Needle electrodes 90 are coupled to power source 24 via
insulated wire 60.
[0094] In another embodiment of treatment apparatus 10 shown in
FIG. 15, needle electrodes 90 are advanced out of apertures 64 in
the body of the device, and/or in basket arms 44. Needle electrodes
may be advanced into the target tissue. For example, the needle
electrodes may be advanced into smooth muscle of the esophageal
wall or other sphincter 16, or the wall of the urethra, or the wall
of some other body lumen. In this case, needle electrodes 90 are
coupled to RF power source 24 by electrode delivery member 60. In
one embodiment, the depth of needle penetration may be selectable
via means of stepped sections 66 or tapered sections 68 located in
apertures 64. Referring to FIG. 16, apertures 64 and needle
electrodes 90 are configured such that the penetration angle 96
(also called an emergence angle 96) of needle electrode 90 into
tissue (e.g., sphincter wall 26) remains sufficiently constant
during the time needle electrode 90 is being inserted into
sphincter wall 26, such that there is no tearing or unnecessary
trauma to sphincter wall tissue. This is facilitated by the
selection of the following parameters and criteria: i) the
emergence angle 96 of apertures 64 which can vary from 1 to
90.degree., ii) the arc radius 98 of the curved section 100 of
aperture 64 which can vary from 0.001 to 2 inch, iii) the amount of
clearance between the aperture inner diameter 102 and the needle
electrode outside diameter 104 which can vary between 0.001'' and
0.1''; and, iv) use of a lubricous coating on electrode delivery
member 60 such as a Teflon.TM. or other coatings well known to
those skilled in the art. Also in this embodiment, insulated
segment 94 can be in the form of a sleeve that may be adjustably
positioned at the exterior of electrode 90.
[0095] In another alternative embodiment shown in FIG. 17,
electrode delivery member 60 with attached needle electrodes 90,
can exit from lumen 36 at distal shaft end 32 and be positioned
into contact with the patient's tissue 26. This process may be
facilitated by use of a hollow guiding member 101, known to those
skilled in the art as a guiding catheter, through which electrode
delivery member 60 is advanced. Guiding catheter 101 may also
include stepped sections 66 or tapered sections 68 at its distal
end to control the depth of penetration of needle electrode 90 into
sphincter wall 26.
[0096] RF energy flowing through tissue causes heating of the
tissue due to absorption of the RF energy by the tissue and ohmic
heating due to electrical resistance of the tissue. This heating
can cause injury to the affected cells and can be substantial
enough to denature collagen, shrink cells or support tissues, and
even cause cell death, a phenomenon also known as cell necrosis.
For ease of discussion for the remainder of this application, cell
injury will include all cellular effects resulting from the
delivery of energy from electrode 88 up to, and including, cell
necrosis. Tissue treatment (including "cell injury") can be
accomplished as a relatively simple medical procedure with local
anesthesia. In one embodiment, cell injury proceeds to a depth of
approximately 1-4 mms from the surface of the mucosal layer of
sphincter 16 or that of an adjoining anatomical structure.
[0097] Referring now to FIGS. 18A, 18B and 18C, electrodes 88
and/or apertures 64 may be distributed in a variety of patterns
along expansion device 20 or basket assembly 50 in order to produce
a desired placement and pattern of lesions 14. Typical electrode
and aperture distribution patterns include, but are not limited to,
a radial distribution 105 (refer to FIG. 18A) or a longitudinal
distribution 106 (refer to FIG. 18B). It will be appreciated that
other patterns and geometries for electrode and aperture placement,
such as a spiral distribution 108 (refer to FIG. 18C) may also be
suitable. These electrodes may be cooled as described
hereafter.
[0098] FIG. 19 is a flow chart illustrating one embodiment of the
procedure for using treatment apparatus 10. In this embodiment,
treatment apparatus 10 is first introduced into the esophagus under
local anesthesia. Treatment apparatus 10 can be introduced into the
esophagus by itself or through a lumen in an endoscope (not shown),
such as disclosed in U.S. Pat. Nos. 5,448,990 and 5,275,608,
incorporated herein by reference, or similar esophageal access
device known to those skilled in the art. Basket assembly 50 is
expanded as described herein. This serves to temporarily dilate the
LES or sufficiently to efface a portion of or all of the folds of
the LES. In an alternative embodiment, esophageal dilation and
subsequent LES fold effacement can be accomplished by insufflation
of the esophagus (a known technique) using gas introduced into the
esophagus through shaft lumen 36, or an endoscope or similar
esophageal access device as described above. Once treatment is
completed, basket assembly 50 is returned to its predeployed or
contracted state and sphincter treatment apparatus 10 is withdrawn
from the esophagus. This results in the LES returning to
approximately its pretreatment state and diameter. It will be
appreciated that the above procedure is applicable in whole or part
to the treatment of other tissues (including other sphincters) in
the body.
[0099] The diagnostic phase of the procedure can be performed using
a variety of diagnostic methods, including, but not limited to, the
following: (i) visualization of the interior surface of the lumen
or tissue wall (e.g., esophagus) via an endoscope or other viewing
apparatus inserted into the lumen, (ii) visualization of the
interior morphology of the lumen wall using ultrasonography to
establish a baseline for the tissue to be treated, (iii) impedance
measurement to determine the electrical conductivity between the
target tissue and intervening tissues (e.g., in esophageal
treatment, the esophageal mucosal layers and sphincter treatment
apparatus 10) and (iv) measurement and surface mapping of the
electropotential of the lumen (e.g., the LES) during varying time
periods which may include such events as depolarization,
contraction and repolarization of wall of the lumen (e.g., LES
smooth muscle tissue). In some examples, this latter technique is
done to determine target treatment sites 12 in the LES or adjoining
anatomical structures that are acting as foci 107 or pathways 109
for abnormal or inappropriate polarization and relaxation of the
smooth muscle of the LES (Refer to FIG. 20).
[0100] In the treatment phase of the procedure, the delivery of
energy to treatment site 12 can be conducted under feedback
control, manually or by a combination of both. Feedback control
(described herein) enables treatment apparatus 10 to be positioned
and retained in the body lumen (e.g., urethra or esophagus) during
treatment with minimal attention by the physician. Electrodes 88
can be multiplexed in order to treat the entire targeted treatment
site 12 or only a portion thereof. Feedback can be included and is
achieved by the use of one or more of the following methods: (i)
visualization, (ii) impedance measurement, (iii) ultrasonography,
(iv) temperature measurement; and, (v) sphincter contractile force
measurement via manometry. The feedback mechanism permits the
selected on-off switching of different electrodes 88 in a desired
pattern, which can be sequential from one electrode 88 to an
adjacent electrode 88, or can jump around between non-adjacent
electrodes 88. Individual electrodes 88 are multiplexed and
volumetrically controlled by a controller.
[0101] The area and magnitude of cell injury in the target tissue
(e.g., LES or sphincter 16) can vary. However, it is desirable to
deliver sufficient energy to the targeted treatment site 12 to be
able to achieve tissue temperatures in the range of 55-95.degree.
C. and produce lesions 14 at depths ranging from 1-4 mms from the
interior surface of the body wall (e.g., LES or sphincter wall 26).
In one variation, typical energies delivered to the esophageal wall
include, but are not limited to, a range between 100 and 50,000
joules per electrode 88. It is also desirable to deliver sufficient
energy such that the resulting lesions 14 have a sufficient
magnitude and area of cell injury to cause an infiltration of
lesion 14 by fibroblasts 110, myofibroblasts 112, macrophages 114
and other cells involved in the tissue healing process (refer to
FIG. 21). As shown in FIG. 22, these cells cause a contraction of
tissue around lesion 14, decreasing its volume and, or altering the
biomechanical properties at lesion 14 so as to result in a
tightening of LES or sphincter 16. These changes are reflected in
transformed lesion 14' shown in FIG. 19B. The diameter of lesions
14 can vary between 0.1 to 4 mms. It is preferable that lesions 14
are less than 4 mms in diameter in order to reduce the risk of
thermal damage to the mucosal layer. In one embodiment, a 2 mm
diameter lesion 14 centered in the wall of the smooth muscle
provides a 1 mm buffer zone to prevent damage to the mucosa,
submucosa and adventitia, while still allowing for cell
infiltration and subsequent sphincter tightening on approximately
50% of the thickness of the wall of the smooth muscle (refer to
FIG. 23).
[0102] In any of the variations of the devices and methods
described herein, it may be beneficial and desirable to image the
anatomic area being treated. For example, it may be beneficial to
image the interior surface and wall of the body region (e.g.,
urethra, LES or other sphincter 16, etc.). Imaging may be performed
before, during and/or after treatment. The size and position of
created treatment regions (e.g., lesions) 14 may be visualized. It
may be desirable to create a map of structures (2D or 3D) which can
be input to a controller and used to direct the delivery of energy
to the treatment site. Referring to FIG. 24, this can be
accomplished through the use of ultrasonography (a known procedure)
which may involve the use of an ultrasound power source 116 coupled
to one or more ultrasound transducers 118 that are positioned on
the devices (e.g., on the expansion device 20 or basket assembly
50), or through the use of miniaturized MR technology. An output is
associated with ultrasound power source 116.
[0103] In general, an imaging modality, including an ultrasound
transducer or miniaturized MR, may be incorporated as part of the
devices and systems described. For example, as mentioned above, an
ultrasound transducer may be used to image the placement location
or position of the device. other imaging modalities may also be
included, such as fiber-optic (light) based transducers and
methods.
[0104] For example, an ultrasound transducer 118 can include a
piezoelectric crystal 120 mounted on a backing material 122 that is
in turn, attached to the device, (e.g., to the expansion device 20
or basket assembly 50). An ultrasound lens 124, fabricated on an
electrically insulating material 126, may be mounted over
piezoelectric crystal 120. Piezoelectric crystal 120 is connected
by electrical leads 128 to ultrasound power source 116. Each
ultrasound transducer 118 transmits ultrasound energy into adjacent
tissue. Ultrasound transducers 118 can be in the form of an imaging
probe such as Model 21362, manufactured and sold by Hewlett Packard
Company, Palo Alto, Calif. In one embodiment, two ultrasound
transducers 118 are positioned on opposite sides of expansion
device 20 or basket assembly 50 to create an image depicting the
size and position of lesion 14 in selected sphincter 16.
[0105] In some variations of the method of treatment described
herein for treatment of a sphincter, it is desirable that
treatments sites (e.g., lesions) 14 are predominantly located in
the smooth muscle layer of selected sphincter 16 at the depths
ranging from 1 to 4 mms from the interior surface of sphincter wall
26. However, lesions 14 can vary both in number and position within
sphincter wall 26. It may be desirable to produce a pattern of
multiple lesions 14 within the sphincter smooth muscle tissue in
order to obtain a selected degree of tightening of the LES or other
sphincter 16. Typical treatment patterns shown in FIGS. 25A-D
include, but are not limited to, (i) a concentric circle of lesions
14 all at fixed depth in the smooth muscle layer evenly spaced
along the radial axis of sphincter 16, (ii) a wavy or folded circle
of lesions 14 at varying depths in the smooth muscle layer evenly
spaced along the radial axis of sphincter 16, (iii) lesions 14
randomly distributed at varying depths in the smooth muscle, but
evenly spaced in a radial direction; and, (iv) an eccentric pattern
of lesions 14 in one or more radial locations in the smooth muscle
wall. Accordingly, the depth of RF and thermal energy penetration
sphincter 16 is controlled and selectable. The selective
application of energy to sphincter 16 may be the even penetration
of RF energy to the entire targeted treatment site 12, a portion of
it, or applying different amounts of RF energy to different sites
depending on the condition of sphincter 16. If desired, the area of
cell injury can be substantially the same for every treatment
event. Similarly, when treating tissues of other body lumen,
including the urethra, the pattern of treatment sites may be
arranged as described above. The pattern may be determined in part
by the arrangement of electrodes extending from the treatment
apparatus. The treatment device may be moved (e.g., repositioned)
to add to or change the pattern of treatment sites.
[0106] Referring to FIG. 26, it may be desirable to cool all or a
portion of the area near the electrode-tissue interface 130 before,
during or after the delivery of energy in order to reduce the
degree and area of cell injury. For example, the use of cooling
preserves the mucosal layers of sphincter wall 26 and protects, or
otherwise reduces the degree of cell damage to cooled zone 132 in
the vicinity of lesion 14. Referring now to FIG. 27, this can be
accomplished through the use of cooling solution 70 that is
delivered by apertures 64 which is in fluid communication with
shaft lumen 36 that is, in turn, in fluid communication with fluid
reservoir 134 and a control unit 136, whose operation is described
herein, that controls the delivery of the fluid.
[0107] Similarly, it may also be desirable to cool all or a portion
of the electrode 88. The rapid delivery of heat through electrode
88, may result in the buildup of charred biological matter on
electrode 88 (from contact with tissue and fluids e.g., blood) that
impedes the flow of both thermal and electrical energy from
electrode 88 to adjacent tissue and causes an electrical impedance
rise beyond a cutoff value set on RF power source 24. A similar
situation may result from the desiccation of tissue adjacent to
electrode 88. Cooling of the electrode 88 can be accomplished by
cooling solution 70 that is delivered by apertures 64 as described
previously. Referring now to FIG. 28, electrode 88 may also be
cooled via a fluid channel 138 in electrode 88 that is in fluid
communication with fluid reservoir 134 and control unit 136.
[0108] As shown in FIG. 29, one or more sensors 140 may be
positioned adjacent to or on electrode 88 for sensing the
temperature of sphincter tissue at treatment site 12. More
specifically, sensors 140 permit accurate determination of the
surface temperature of sphincter wall 26 at electrode-tissue
interface 130. This information can be used to regulate both the
delivery of energy and cooling solution 70 to the interior surface
of sphincter wall 26. In various embodiments, sensors 140 can be
positioned at any position on expansion device 20 or basket
assembly 50. Suitable sensors that may be used for sensor 140
include: thermocouples, fiber optics, resistive wires, thermocouple
IR detectors, and the like. Suitable thermocouples for sensor 140
include: T type with copper constantene, J type, E type and K types
as are well known those skilled in the art.
[0109] Temperature data from sensors 140 may be fed back to control
unit 136 and through an algorithm which is stored within a
microprocessor memory of control unit 136. Instructions are sent to
an electronically controlled micropump (not shown) to deliver fluid
through the fluid lines at the appropriate flow rate and duration
to provide control temperature at the electrode-tissue interface
130 (refer to FIG. 27).
[0110] The reservoir of control unit 136 may have the ability to
control the temperature of the cooling solution 70 by either
cooling the fluid or heating the fluid. Alternatively, a fluid
reservoir 134 of sufficient size may be used in which the cooling
solution 70 is introduced at a temperature at or near that of the
normal body temperature. Using a thermally insulated reservoir 142,
adequate control of the tissue temperature may be accomplished
without need of refrigeration or heating of the cooling solution
70. Cooling solution 70 flow is controlled by control unit 136 or
another feedback control system (described herein) to provide
temperature control at the electrode-tissue interface 130.
[0111] A second diagnostic phase may be included after the
treatment is completed. This provides an indication of LES
tightening treatment success, and whether or not a second phase of
treatment, to all or only a portion of the esophagus, now or at
some later time, should be conducted. The second diagnostic phase
is accomplished through one or more of the following methods: (i)
visualization, (ii) measuring impedance, (iii) ultrasonography,
(iv) temperature measurement, or (v) measurement of LES tension and
contractile force via manometry.
[0112] In one embodiment, sphincter treatment apparatus 10 is
coupled to an open or closed loop feedback system. Referring now to
FIG. 30, an open or closed loop feedback system couples sensor 346
to energy source 392. In this embodiment, electrode 314 is one or
more RF electrodes 314.
[0113] The temperature of the tissue, or of RF electrode 314 is
monitored, and the output power of energy source 392 adjusted
accordingly. The physician can, if desired, override the closed or
open loop system. A microprocessor 394 can be included and
incorporated in the closed or open loop system to switch power on
and off, as well as modulate the power. The closed loop system
utilizes microprocessor 394 to serve as a controller, monitor the
temperature, adjust the RF power, analyze the result, refeed the
result, and then modulate the power.
[0114] With the use of sensor 346 and the feedback control system a
tissue adjacent to RF electrode 314 can be maintained at a desired
temperature for a selected period of time without causing a
shutdown of the power circuit to electrode 314 due to the
development of excessive electrical impedance at electrode 314 or
adjacent tissue as is discussed herein. Each RF electrode 314 is
connected to resources which generate an independent output. The
output maintains a selected energy at RF electrode 314 for a
selected length of time.
[0115] Current delivered through RF electrode 314 is measured by
current sensor 396. Voltage is measured by voltage sensor 398.
Impedance and power are then calculated at power and impedance
calculation device 400. These values can then be displayed at user
interface and display 402. Signals representative of power and
impedance values are received by a controller 404.
[0116] A control signal is generated by controller 404 that is
proportional to the difference between an actual measured value,
and a desired value. The control signal is used by power circuits
406 to adjust the power output in an appropriate amount in order to
maintain the desired power delivered at respective RF electrodes
314.
[0117] In a similar manner, temperatures detected at sensor 346
provide feedback for maintaining a selected power. Temperature at
sensor 346 is used as a safety means to interrupt the delivery of
energy when maximum pre-set temperatures are exceeded. The actual
temperatures are measured at temperature measurement device 408,
and the temperatures are displayed at user interface and display
402. A control signal is generated by controller 404 that is
proportional to the difference between an actual measured
temperature and a desired temperature. The control signal is used
by power circuits 406 to adjust the power output in an appropriate
amount in order to maintain the desired temperature delivered at
the sensor 346. A multiplexer can be included to measure current,
voltage and temperature, at the sensor 346, and energy can be
delivered to RF electrode 314 in monopolar or bipolar fashion.
[0118] Controller 404 can be a digital or analog controller, or a
computer with software. When controller 404 is a computer it can
include a CPU coupled through a system bus. This system can include
a keyboard, a disk drive, or other non-volatile memory systems, a
display, and other peripherals, as are known in the art. Also
coupled to the bus is a program memory and a data memory.
[0119] User interface and display 402 includes operator controls
and a display. Controller 404 can be coupled to imaging systems
including, but not limited to, ultrasound, CT scanners, X-ray, MRI,
mammographic X-ray and the like. Further, direct visualization and
tactile imaging can be utilized.
[0120] The output of current sensor 396 and voltage sensor 398 are
used by controller 404 to maintain a selected power level at RF
electrode 314. The amount of RF energy delivered controls the
amount of power. A profile of the power delivered to electrode 314
can be incorporated in controller 404 and a preset amount of energy
to be delivered may also be profiled.
[0121] Circuitry, software and feedback to controller 404 result in
process control, the maintenance of the selected power setting
which is independent of changes in voltage or current, and is used
to change the following process variables: (i) the selected power
setting, (ii) the duty cycle (e.g., on-off time), (iii) bipolar or
monopolar energy delivery; and, (iv) fluid delivery, including flow
rate and pressure. These process variables are controlled and
varied, while maintaining the desired delivery of power independent
of changes in voltage or current, based on temperatures monitored
at sensor 346.
[0122] Referring now to FIG. 31, current sensor 396 and voltage
sensor 398 are connected to the input of an analog amplifier 410.
Analog amplifier 410 can be a conventional differential amplifier
circuit for use with sensor 346. The output of analog amplifier 410
is sequentially connected by an analog multiplexer 412 to the input
of A/D converter 414. The output of analog amplifier 410 is a
voltage which represents the respective sensed temperatures.
Digitized amplifier output voltages are supplied by A/D converter
414 to microprocessor 394. Microprocessor 394 may be a type 68HCII
available from Motorola. However, it will be appreciated that any
suitable microprocessor or general purpose digital or analog
computer can be used to calculate impedance or temperature.
[0123] Microprocessor 394 sequentially receives and stores digital
representations of impedance and temperature. Each digital value
received by microprocessor 394 corresponds to different
temperatures and impedances.
[0124] Calculated power and impedance values can be indicated on
user interface and display 402. Alternatively, or in addition to
the numerical indication of power or impedance, calculated
impedance and power values can be compared by microprocessor 394 to
power and impedance limits. When the values exceed predetermined
power or impedance values, a warning can be given on user interface
and display 402, and additionally, the delivery of RF energy can be
reduced, modified or interrupted. A control signal from
microprocessor 394 can modify the power level supplied by energy
source 392.
[0125] FIG. 32 illustrates a block diagram of a temperature and
impedance feedback system that can be used to control the delivery
of energy to tissue site 416 by energy source 392 and the delivery
of cooling solution 70 to electrode 314 and/or tissue site 416 by
flow regulator 418. Energy is delivered to RF electrode 314 by
energy source 392, and applied to tissue site 416. A monitor 420
ascertains tissue impedance, based on the energy delivered to
tissue, and compares the measured impedance value to a set value.
If the measured impedance exceeds the set value, a disabling signal
422 is transmitted to energy source 392, ceasing further delivery
of energy to RF electrode 314. If measured impedance is within
acceptable limits, energy continues to be applied to the
tissue.
[0126] The control of cooling solution 70 to electrode 314 and/or
tissue site 416 is done in the following manner. During the
application of energy, temperature measurement device 408 measures
the temperature of tissue site 416 and/or RF electrode 314. A
comparator 424 receives a signal representative of the measured
temperature and compares this value to a pre-set signal
representative of the desired temperature. If the tissue
temperature is too high, comparator 424 sends a signal to a flow
regulator 418 (connected to an electronically controlled micropump,
not shown) representing a need for an increased cooling solution
flow rate. If the measured temperature has not exceeded the desired
temperature, comparator 424 sends a signal to flow regulator 418 to
maintain the cooling solution flow rate at its existing level.
[0127] Although the examples illustrated above refer primarily to
methods of treating a sphincter, the devices, systems and methods
described herein may be used to treat other tissues. In particular,
as mentioned above, the devices and systems may be used to treat
urinary incontinence by treatment of a subject's urethra. For
example, FIG. 33 shows a block diagram of one variation of a method
for treating urinary incontinence by applying heat to treat a
urethra using the devices described herein. For example, a method
of treating a urethra may include delivering energy to a portion of
the urethra in an annular pattern of circumferentially spaced-apart
treatment sites in the tissue in a patient's urethra by: (1)
providing a treatment device having a plurality of tissue-piercing
needle electrodes configured to extend from the treatment device
and an expandable member at the distal end of the treatment device;
(2) advancing the treatment device distally within a patient's
urethra 3301; (3) expanding an expandable member at the distal end
of the treatment device within the patient's bladder 3303; (4)
applying a slight downward force to position the electrodes below
the bladder neck 3305, and to seat the expandable region distally
at the bladder outlet; (5) extending the tissue-piercing needle
electrodes from the treatment device into the tissue 3307; (6) and
delivering RF energy from the needle electrodes 3309 resulting in
an annular pattern of individual, circumferentially spaced-apart
tissue regions. The energy may be applied to a temperature (e.g.,
between 50.degree. C. and 60.degree. C.) to denature the collagen
in the region near the tips of the needle electrodes without
causing substantial necrosis. In some variations, the method may
also include the step of (7) monitoring the temperature of the
tissue near the electrodes 3311 and feeding temperature information
back into the controller to regulate the applied power. Fluid
(e.g., water) may also be applied to cool the tissue at non-treated
(e.g., adjacent) sites 3313 before, during and/or after delivery of
energy to treat the tissue. Once this first pass has been
completed, the electrodes may be withdrawn, and the device
repositioned 3315, and the electrodes extended and powered again
3317, until the desired annular pattern of treatment sites is
achieved. In FIG. 33, optional steps are indicated by dashed
boxed.
[0128] The foregoing description of a preferred embodiment of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise forms disclosed. Obviously, many
modifications and variations will be apparent to practitioners
skilled in this art. It is intended that the scope of the invention
be defined by the following claims and their equivalents.
* * * * *